Combined pulse generator and odometer assembly for a railway locomotive

ABSTRACT

A combined rotary pulse generator and odometer assembly for the axle of a railway locomotive simultaneously generates a speedindicative electrical signal and digitally totalizes mileage traveled. The assembly includes a pulse generator which has a shaft coupled to the end of a locomotive axle to develop electrical pulses as the axle turns. A novel odometer assembly, mounted on the cover plate of the pulse generator, converts the rotary motion of the generator shaft to oscillating motion to drive a digital mileage counter and record accumulated mileage for the locomotive. The odometer assembly is easily converted to accommodate different sizes of drive wheels and different units of distance, and the digital accumulated mileage display is positioned for maximum legibility under poor lighting conditions.

United States Patent [191 Myrent et al.

[ Dec. 18, 1973 COMBINED PULSE GENERATOR AND ODOMETER ASSEMBLY FOR ARAILWAY LocoMoTrvE [75] Inventors: Barry L. Myrent, Wilmette; Chester H.Fluder, Wheeling, both of III.

[73] Assignee: Vapor Corporation, Chicago, Ill.

[22] Filed: Oct. 11, 1972 [21] Appl. No.: 296,513

[52] U.S. Cl. 73/490, 235/95 R [51] Int. Cl G0lc 23/00, G0lc 22/00 [58]Field of Search 73/490, 493; 235/95 B, 95 R [56] References CitedFOREIGN PATENTS OR APPLICATIONS 698,937 l0/l953 Great Britain 235/95 R698,869 10/1952 Great Britain 235/95 R Primary Examiner--James J. GillAtt0rneyLloyd L. Zickert 5 7 ABSTRACT A combined rotary pulse generatorand odometer assembly for the axle of a railway locomotivesimultaneously generates a speed-indicative electrical signal anddigitally totalizes mileage traveled. The assembly includes a pulsegenerator which has a shaft coupled to the end of a locomotive axle todevelop electrical pulses as the axle turns. A novel odometer assembly,mounted on the cover plate of the pulse generator, converts the rotarymotion of the generator shaft to oscillating motion to drive a digitalmileage counter and record accumulated mileage for the locomotive. Theodometer assembly is easily converted to accommodate different sizes ofdrive wheels and different units of distance, and the digitalaccumulated mileage display is positioned for maximum legibility underpoor lighting conditions.

5 Claims, 6 Drawing Figures PATENTEU 3.7753 O86 sum 1 OF 3 PAIENTEBBEM W3 779 08s SHEET 2 [IF 3 I PATENTEBUELI 813' I saw 3 OF 3 COMBINED PULSEGENERATOR AND ODOMETER ASSEMBLY FOR A RAILWAY LOCOMOTIVE The presentinvention relates in general to odometers for railway vehicles, and moreparticularly to a combined pulse generator and odometer assembly for theaxle of a railway locomotive.

In the operation of railway locomotives it is often desirable to knowthe actual distance a locomotive has traveled over a given period oftime. This information can not only indicate the need for programmedpreventative maintenance as the locomotive accumulates miles, but canalso provide a valuable statistical input to maintenance and otheroperational records associated with the locomotive. To be most useful,this information should be available from outside of the locomotive, andshould be presented in a form which is easily readable, even in thedimly lit environoment of a freight yard or train station.

It is also desirable in the operation of locomotives to know the rate oftravel of the locomotive for obvious reasons of safety and efficiency ofoperation. To this end rate-of-travel indicators, either of themechanical type wherein a flexible drive shaft is run from a pickup onthe wheel to a mechanical speedometer in the cab, or of the electricaltype, such as the Vapor Corporation SPEED-LOG, wherein a pulsegenerating pickup on the wheel drives an electrical indicator within thelocomotive, have been provided on locomotives.

In either case, the functions of totalizing mileage and measuring speedhave heretofore been accomplished by means of separate apparatusdisposed on separate axle bearings of the locomotive. This has beennecessary because prior-art odometers, including both axlemounted andcab-type odometers, required a direct drive from the locomotive axle,precluding their concurrent use with a magnetic pulse generator ormechanical pickup on the same axle bearing. Unfortunately, thisunnecessarily complicated repair work and added to the complexity andcost of manufacture of the locomotive.

The present invention is generally directed to a combined pulsegenerator-odometer assembly for installation on the journal box of arailway vehicle axle. The assembly generally comprises a rotary pulsegenerator for generating a speed signal, and an odometer for measuringdistance traveled both forward and backward. The generator is coupled toand driven by the axle, and the odometer is coupled to an driven by thegenerator.

The assembly more specifcally comprises a rotary pulse generator havinga body portion disposed within the journal box, a drive shaft rotatablycoupled to the axle, and a cover plate adapted to mount on and enclosethe body portion. The odometer includes a digital counter mounted on thecover plate having an input shaft responsive to oscillating motion forcausing the counter to advance to higher counting states. An odometerdrive shaft is provided extending through the generator cover plate andinto rotational engagement with the pulse generator drive shaft, and aworm-drive gear is mounted on the odometer drive shaft. A wormfollowergear operatively engages the worm drive gear 60, and means responsive tothe rotary motion of the worm-follower gear 61 are provided foroscillating the digital counter input shaft to periodically advance thecounter while the locomotive is in motion.

Accordingly, it is a general object of the present invention to providea combined pulse generator and odometer assembly for installation on thejournal of a railway locomotive drive truck.

It is a more specific object of the present invention to provide a newand improved unitary pulse generator and distance recording odometer fora railway locomotive which is rugged, completely enclosed and whichpresents a narrow profile so as to not interfere with operation of thelocomotive.

It is still another specific object of the present invention to providea new and improved odometer for the axle of a railway locomotive whichprovides a digital presentation of total mileage which can be read fromoutside the locomotive under poor ambient light conditions.

Other objects, features and advantages of the invention will be apparentfrom the following detailed disclosure, taken in conjunction with theaccompanying sheets of drawings, wherein like reference numerals referto like parts, in which:

FIG. l is a side view of the front portion of a railway locomotivehaving a drive truck which incorporates a combined pulse generator andodometer assembly constructed in accordance with the present invention.

FIG. 2 is a front view of the drive wheel and journal box of the drivetruck of FIG. I on which the combined pulse generator and odometerassembly of the present invention is installed.

FIG. 3 is a fragmentary cross-sectional side view of the drive wheel andjournal box of FIG. 2 showing the combined pulse generator and odometerof the present invention.

FIG. 4 is a side view, partially in section, of a combined pulsegenerator and odometer assembly constructed in accordance with theinvention.

FIG. 5 is a front elevational view, partially in section, of a combinedpulse generator and odometer assembly constructed in accordance with theinvention.

FIG. 6 is a cross-sectional view taken along lines 6-6 of FIG. 5.

Referring to FIGS. 1-3, a combined pulse generator and odometer assemblyis shown installed on the front axle of a railway locomotive 10. Thelocomotive may be conventional in design and construction, having a cabcompartment 11 and one or more drive trucks 12. The drive trucks mayalso be of conventional design and construction, having a trio of axles13, each carrying a flanged drive wheel 14 on either end for engagementwith a rail 15. The axles are held in spaced-apart relationship abovethe rail by a truck carriage 16 which supports the locomotive bodythrough a plurality of spring members 17.

The axles 13 are rotatably supported by journal bearings 18 mounted inthe truck carriage 16. The wheels 14 are carried on the axles inside ofand adjacent the journal bearings. The carriage is extended in front ofeach journal bearing to form a journal box 19, which may be packed withgrease or other lubricant, and which is normally covered with a journalcover plate 20 to retain its grease packing and prevent dust and dirtfrom entering.

In accordance with the invention the center wheel of the front rightdrive truck of the locomotive is fitted with a combined pulse generatorand odometer assembly 21. This novel assembly produces speed-indicativeelectrical output pulses as the locomotive moves, while simultaneouslyrecording total mileage. The speedindicative pulses are generated in arotary pulse generator portion 22 of the assembly, and applied by meansof a conductor 23 to a speed indicator 24, which may be mounted in viewof the operator in cab 11. Totalized mileage is recorded by means of adigital odometer portion 25 of the assembly, which is illustrated indetail in FIG. 4.

The combined pulse generator and odometer assembly 21 is secured to thefront of journal box 19 by means of a plurality of nut and boltassemblies or fasteners 26, the journal box cover 20 being first removedand the back plate of the combined assembly being mounted in its place.It is also necessary to mechanically couple axle 13 to the combinedassembly 21. This may be conveniently accomplished by providing aflexible coupling member 27 between the input shaft of the pulsegenerator and the end of the axle. While the coupling can be attached tothe axle by any convenient means, it has been found convenient toutilize a threaded spline attachment to the end of the axle, since thisarragnement is readily installed in the field and permits assembly 21 tobe readily removed for repair or replacement.

Reference is now made'to FIG. 4, which shows the combined pulsegenerator and odometer assembly 21 of the invention in partialcross-section. There, the pulse generator portion 22 of the assembly isseen to generally comprise housing 28 which rotatably supports a rotorshaft 29 having a rotor 30 mounted thereon, a stator 31 which is fixedin the housing in coacting relation to the rotor 30, and a coil assembly32 which responds to the changing flux density of a magnetic fieldgenerated and produces an electrical output signal. The rotor shaft,rotor and stator are of magnetic material. This signal is applied to aterminal strip 33, from which it is carried by conductor 23 to thelocomotive speed indicating apparatus. As we have previously seen, therotor shaft 29 is coupled directly to the axle 13 of the locomotive bycoupling 27.

The housing 28 includes a hub portion having a bearing 34 for supportingrotor shaft 29. The bearing is maintained in position by a retainingring 35 at one end and a cover plate 36 at the other end. A shoulder 37is formed on the rotor shaft to cooperate with a lock nut 38 threaded onthe shaft to lock the shaft to the inner race of the bearing 34. Theouter free end of the rotor shaft 29 is preferably flattened orotherwise formed to facilitate coupling it to the locomotive axle.

Both the rotor 30 and the stator 31 are formed by securing a pluralityof laminations together by riveting or other suitable means. The rotoris secured to a flange 39 on the rotor shaft by a plurality of fasteners40 and the stator is secured to housing 28 by a plurality of fasteners41. The exterior edge or periphery of the laminated rotor and the innerperiphery of the stator are formed to define a plurality ofcircumferentially spaced teeth. These teeth are of equal spacing andequal numbet, and are arranged in radial alignment so they will matchand mismatch as the axle revolves.

Coil assembly 32 responds to the periodic changes in magnetic fieldintensity as the magnetic circuit is periodically established andinterrupted to generate an electrical signal for the speed indicatingequipment. The coil assembly includes a bobbin 42, a coil winding 43,and a plurality of permanent magnets 44. The bobbin 42 is constructed ofa magnetic core 45, a circular non-magnetic electrically conductivefront plate 46, and a circular magnetic back plate 47.

The permanent magnets 44 are cylindrical in shape and abut at one endthe magnetic back plate 47, and extend through openings formed in thefront plate 46 to bear against one side of the stator 31. The rear endof the rotor shaft 29 extends through the coil assembly, and to furthersupport the end of the rotor shaft associated with the coil assembly, asleeve bearing 48 is mounted under the bobbin 42. A mounting flang 49 isformed integrally with the annular wall of the housing 28 and isprovided with a plurality of holes 50 to receive fasteners 26 and tofacilitate mounting the generator to a locomotive journal box. Housing28 is closed at its rear end by a generator cover member 51 which issecured thereto by a plurality of machine bolts 52. Cover member 51includes on its outer surface an integrally formed junction box 53within which is mounted terminal strip 33. An access plate 54 secured bya plurality of wire-locked machine screws 55 permits access to theterminal strip box.

In operation, an output signal is obtained from the generator when thelocomotive axle causes rotor shaft 29 and rotor 30 to rotate. Thepermanent magnets 44 produce a magnetic filed which loops through thestator 31, the rotor 30, the rotor shaft 29 and the back plate 47 of thecoil assembly. Matching and mismatching of the teeth on the rotor andstator change the flux density of this magnetic filed and generate acurrent inwinding 43, the frequency of which depends on the number ofteeth on the stator and rotor. The nonmagnetic front plate 46 acts as ashorted turn to limit the peak-to-peak output voltage, which couldotherwise cause darnage to the input stages in the electronic speeddisplay instruments associated with the pulse generator.

In accordance with the invention, the combined pulse generator andodometer of the present invention includes a novel digital mileagetotalizing assembly, as seen in cross-section in H6. 4. Basically, thismechanism comprises an odometer drive shaft 56 rotatably mounted in asleeve bearing 57 carried by the generator cover plate 51. The shaft 56extends through the cover plate, and is coaxial with and rotationallycoupled to the generator drive shaft by means of a fork member 58carried on the generator shaft and a cooperating clevis member 59disposed on the end of the odometer drive shaft. This effectivelycouples the two shafts but yet allows them to be separated should itbecome necessary to remove mounting plate 51 for maintenance of thepulse generator.

A worm-drive gear 60 is mounted near the end of shaft 56. This gearmeshes with a worm-follower gear 61, which, referring to FIGS. 5 and 6,is mounted on a shaft 62 between two spaced-apart sleeve bearings 63 and64, which comprise part of a unitary shaft support assembly 65. Therotary motion of shaft 62 is converted to oscillating motion by means ofa slot-crank type geneva movement. This movement comprises a wheel 66mounted on the end of shaft 62 adjacent bearing 64. An eccentric pin 67,mounted off-center on the wheel 66 engages a slot on one end of a crankarm 68, the other end of which is fixed to the input shaft 69 of adigital counter or odometer assembly 70.

In operation, as the locomotive moves odometer drive shaft 56 rotates,causing worm-drive gear 60 to drive worm-follower gear 61 at a reducedspeed, typically with a net reduction of approximately 50:] for mileageindications and 30:1 for kilometer indications. The exact ratio betweenthe two speeds is dependent on the ratio between gears 60 and 61 and isselected to provide an accurate mileage indication on the particularcounter used. As worm-follower gear 61 rotates, it rotates shaft 62which causes wheel 66 to rotate. This causes crank arm 68 to oscillateabout its pivot point on shaft 69 as its slotted end follows pin 67,imparting an oscillating motion to the shaft. Digital counter 70responds to this input by advancing its count one step or one-tenthdivision for each oscillation. Thus, the counter advances one mile foreach 500 revolutions of the locomotive drive axle, or one kilometer foreach 300 revolutions of the drive axle.

Counter 70 may be entirely conventional in design and operation, andtherefore need not be shown in further detail. It suffices in thisparticular embodiment of the invention that counter 70 responds bycounting in one-tenth units to oscillating motion applied to its inputshaft, in contrast to those counters responding to full revolutions. Acover 71 is mounted on cover plate 51 by a plurality of machine screws72 to provide a weather-tight protective covering for the odometerassembly. This cover may contain a window 73 through which the digits ofcounter 70 can be conveniently viewed, and an enlarged portion foraccomodating the gears and geneva assembly of the odometer mechanism.

The use of the aforedescribed gear arrangement for driving counter 70 isparticularly attractive because of the low profile it provides on theoutside of the journal box, while permitting the digits of the counterto be readily viewed, even in dimly-lit yard and terminal areas. Theodometer assembly can be made to readily accommodate various units ofmeasurement and wheel sizes by merely changing worm-drive gear 60 andworm-follower gear 61, which are readily accessible by removing cover71. Furthermore, this gear arrangement provides increased reliabilitysince the counter and the reduction gears are not required to operate athigh axle speeds.

Thus, a novel axle-mounted assembly has been shown for a railwaylocomotive which produces pulses at a rate dependent on the speed of thelocomotive, while at the same time totatlizing mileage traveled. It doesthis with only one connection to the axle of the comotive for ease ofinstallation and maintenance. The assembly presents a minimum profileabove the journal box so as not to interfere with normal operation ofthe locomotive, and is easily adapted to differnent types of locomotivesand distance units, e.g. miles or kilometers, by merely changing twogears.

It will be understood that medications and variations may be effectedwithout departing from the scope of the novel concepts of the presentinvention, but it is understood that this application is to be limitedonly by the scope of the appended claims.

This invention is hereby claimed as follows:

1. A combined pulse generator-odometer assembly for installation on thejournal box of a railway vehicle axle, comprising a rotary pulsegenerator and an odometer:

said rotary pulse generator having a body portion adapted to be mountedwithin said journal box, a drive shaft rotatably coupled to said axle,and a cover plate adapted to mount on and enclose said body portion;

said odometer including a digital counter mounted on said cover plateand having an input shaft responsive to oscillating motion for causingthe counter to advance to high counting states;

an odometer drive shaft extending through said generator cover plate andinto rotational engagement with said pulse generator drive shaft;

a worm-drive gear mounted on said odometer drive shaft;

a worm-follower gear operatively engaged with said worm-drive gear; and

means responsive to the rotation of said wormfollower gear foroscillating said digital counter input shaft to periodically advancesaid counter while said locomotive is in motion.

2. A combine pulse generator-odometer assembly as defined in claim 1wherein said means for oscillating said digital counter shaft comprisesa slot-crank geneva movement.

3. A combined pulse generator-odometer assembly as defined in claim 2wherein said slot-crank geneva movement comprises a wheel, a pin mountedoff-center on said wheel, and a crank arm having one end coupled to saidodometer input shaft and having a slot at the other end slidablyreceiving said pin.

4. A combined pulse generator-odometer assembly as defined in claim 3wherein said odometer input shaft is disposed parallel to the plane ofsaid cover plate and at right angles to said odometer drive shaft.

5. A combined pulse generator-odometer assembly as defined in claim 1wherein said odometer drive shaft is coupled to said generator driveshaft by means of a fork and clevis assembly.

1. A combined pulse generator-odometer assembly for installation on thejournal box of a railway vehicle axle, comprising a rotary pulsegenerator and an odometer: said rotary pulse generator having a bodyportion adapted to be mounted within said journal box, a drive shaftrotatably coupled to said axle, and a cover plate adapted to mount onand enclose said body portion; said odometer including a digital countermounted on said cover plate and having an input shaft responsive tooscillating motion for causing the counter to advance to high countingstates; an odometer drive shaft extending through said generator coverplate and into rotational engagement with said pulse generator driveshaft; a worm-drive gear mounted on said odometer drive shaft; aworm-follower gear operatively engaged with said worm-drive gear; andmeans responsive to the rotation of said worm-follower gear foroscillating said digital counter input shaft to periodically advancesaid counter while said locomotive is in motion.
 2. A combine pulsegenerator-odometer assembly as defined in claim 1 wherein said means foroscillating said digital counter shaft comprises a slot-crank genevamovement.
 3. A combined pulse generator-odometer assembly as defined inclaim 2 wherein said slot-crank geneva movement comprises a wheel, a pinmounted off-center on said wheel, and a crank arm having one end coupledto said odometer input shaft and having a slot at the other end slidablyreceiving said pin.
 4. A combined pulse generator-odometer assembly asdefined in claim 3 wherein said odometer input shaft is disposedparallel to the plane of said cover plate and at right angles to saidodometer drive shaft.
 5. A combined pulse generator-odometer assembly asdefined in claim 1 wherein said odometer drive shaft is coupled to saidgenerator drive shaft by means of a fork and clevis assembly.